How is the efficiency of heating and cooling equipment measured?
When purchasing a furnace, heat pump or air conditioner, ALWAYS ask about its Efficiency Ratings. They will tell you will tell you how efficiently the unit uses fuel (gas, oil or electricity). The most-frequently used efficiency ratings are:
When considering a new system, your AC contractor should always perform a Load calculation on your home before recommending new equipment. Going by the size of the previous system can be unwise as the previous system might
not have been calculated properly. It's also possible that changes to the home have increased or decreased your homes efficiency.